This is a C.B. adjustable table telephone.

The telephone comprises of a handset (Telephone No. 78) and a base (Stand, Table, for Telephone No. 78) or a wall hook (Suspender, micro-telephone, No. 2).

The handset had a switch that muted the transmitter in the normal position.

There is no documentation for this telephone but the diagram intimates that the handset is a self contained unit, which included an internal switch hook.  To operate the switch hook the handset would be hang on a stand or a wall hook.  It is also debatable as to why it is called an adjustable telephone.

Made by the Western Electric Co. (Model 4005).

Used with Bellset No. 1.

A C.B. version of this telephone was tested by the BPO in 1915 and the dial variant probably introduced in the late 1920's if at all.

The picture is dated 1927.

Telephone includes (1928):-
1 x Connection, Mouthpiece No. 5.
1 x Cord, Instrument No. 342.
1 x Earpiece No. 2.
1 x Mouthpiece No. 12.
1 x Transmitter, Inset No. 1.

To be requisitioned separately :-
1 x Suspender, micro-telephone, No. 2, or
1 x Stand, Table, for Telephone No. 78.

Circuit diagram - N178.

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Last revised: February 07, 2023